Mechanisms of mRNA and sn(o)RNA Synthesis in Saccharomyces cerevisiae
The synthesis of functional mRNA templates for protein expression and of a large number of small and stable sn(o)RNAs requires transcription by RNA polymerase II and extensive RNA processing. Recent advances in the understanding of both transcription and of RNA processing revealed intimate connections between these processes in vivo. Elongating RNA polymerase II not only integrates the chromatin template and the RNA transcript, but also a large number of associated protein factors including RNA processing enzymes. Remarkably, processing factors impact heavily on transcription and vice versa, transcription factors can profoundly influence processing. To increase the understanding of transcription and of RNA processing it is necessary to analyze the production of mature RNAs with the consideration that these processes are highly interdependent in vivo. We will functionally analyze RNAP II elongation complexes with the aim to better understand the mechanisms and regulation of mRNA and sn(o)RNA synthesis. Major goals of our work are: 1) to identify novel factors that associate with RNAP II during transcription and to understand how they function in transcription and/or RNA processing; 2) to elucidate the molecular mechanisms that act during termination of processive RNA synthesis by RNA polymerase II; 3) to understand how 3’ end formation factors influence elongating RNA polymerase II during different steps of the transcription cycle.
We use the yeast Saccharomyces cerevisiae as a model system for analyses since it can be manipulated with ease. The genetic, biochemical and proteomic methodologies and tools available for yeast are strongly superior to other eukaryotic model organisms currently studied. Importantly, the insights gained from the yeast system most certainly will provide important knowledge for RNA synthesis also in higher eukaryotes (including humans) since many of the basic biochemical mechanisms and the factors involved are conserved in evolution.